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Top positive review

This review is specifically for the item SanDisk Extreme 128GB microSD UHS-I Card with Adapter - 160MB/s with SanDisk MobileMate USB 3.0 microSD Card Reader. My card was shipped from and sold by Amazon.com. The top review for this card would have you believe the product I received, based on physical appearance, is fake. The speed tests and H2testw program appear to indicate it achieves the advertised speeds and has the correct capacity using the bundled USB 3.0 card reader in a USB 3.0 port on my desktop Windows 10 PC.If this card is somehow "fake" it is quite impressive. I'm sure there are some fakes out there, but if you do decide to buy this card it might be worth performing your own tests before deeming it fake based off the looks alone (assuming it's not an incredibly obvious fake).April 18, 2020 (13 month update): card still works great. No complaints, I'm very happy with it.

Top critical review

First red flag was when I looked underneath the card. Instead of being solid black like every other SD card I've seen, it looked like a green circuit board with a strange black square on it.

Second red flag was the MUCH lower than advertised read/write speeds (only 50-55 write with mid 80s read).

Third red flag was when I tried to copy data from my old sd card on to this one. I was able to get about 21.5 GB of data on to it until it unmounted itself from my computer. I then physically removed the card and inserted it back in the computer. Windows recommended that I repair the drive, so I did. After that, I go and try to copy the data again and it unmounted itself, just like before. I tried the same thing by repairing the drive, except this time, Windows informs me that it could not be repaired! Seriously??

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I often forget that companies for simplicity years ago decided to market storage data this way. This is my first large micro sd card so really I hadn't the loss in storage till now; which is around 5%. So you're getting around 475gb rather than 512gb. This is because 1000mb does not make 1gb, but 1024mb is 1gb. That 24mb difference is next to nothing on small storage cards, though with the rule of large numbers the higher you go the more you lose and it adds up/subtracts from the advertised size. In this case it's 37gb of lost storage. I have no idea why this hasn't been fixed by now. Storage space and batteries are possibly the only products that can lie on their package about their capacity, and not be reprimanded for it. I'm sure the people who buy the 1tb cards aren't thrilled when they see 74gb missing either.Outside of that the card works great and haven't had any problems with it as of yet. I just think now that we have even larger cards than this, that companies would acknowledge the loss and advertise the cards appropriately.